HHS Special Exposure Cohort Designation:

Clinton Engineer Works, Oak Ridge, Tennessee

HHS Designation of Additional Members of the 

Special Exposure Cohort 

under the 

Energy Employees Occupational Illness Compensation Program Act of 2000 

Designating a Class of Employees from 

Clinton Engineer Works

Oak Ridge, Tennessee
HHS Special Exposure Cohort Designation:

Clinton Engineer Works, Oak Ridge, Tennessee

Page 2

I. Designation 

I, Kathleen Sebelius, Secretary of Health and Human Services, designate the class 

of employees defined in Section II of this report for addition to the Special Exposure 

Cohort (SEC), as authorized under the Energy Employees Occupational Illness 

Compensation Program Act of 2000 (EEOICPA), 42 U.S.C. § 7384q.

___May 11, 2012_____ __[Signature on file]____________

Date Kathleen Sebelius

II. Employee Class Definition

All employees of the Tennessee Eastman Corporation (1943-1947) and the 

Carbide and Carbon Chemicals Corporation (1947-1949) who were employed 

at the Clinton Engineer Works in Oak Ridge, Tennessee, from January 1, 

1943 through December 31, 1949 for a number of work days aggregating at 

least 250 work days, occurring either solely under this employment or in 

combination with work days within the parameters established for one or 

more classes of employees included in the Special Exposure Cohort.

III. Designation Criteria and Recommendations

Pursuant to 42 U.S.C. § 7384q, for the class defined in Section II of this report, the 

Secretary has determined, and the Advisory Board on Radiation and Worker Health 

(Board) has recommended, that

(1) it is not feasible to estimate with sufficient accuracy the radiation dose that the 

class received; and

(2) there is a reasonable likelihood that such radiation dose may have 

endangered the health of members of the class.

The SEC final rule states in 42 C.F.R. § 83.13(c)(1) that it is feasible in two situations 

to estimate the radiation dose that the class received with sufficient accuracy. First, 

the rule states that radiation doses may be estimated with sufficient accuracy if 

NIOSH has established that it has access to sufficient information to estimate the 

maximum radiation dose for every type of cancer for which radiation doses are 

reconstructed that could have been incurred under plausible circumstances by any 

member of the class. Alternatively, radiation doses may be estimated with sufficient 

accuracy if NIOSH has established that it has access to sufficient information to 

estimate the radiation doses of members of the class more precisely than a 

maximum dose estimate.

The Board, pursuant to 42 U.S.C. § 7384q, advised the Secretary to designate the 

class as an addition to the SEC in a letter received by the Secretary on April 11, 

2012.
HHS Special Exposure Cohort Designation:

Clinton Engineer Works, Oak Ridge, Tennessee

Page 3

IV. Designation Findings

Feasibility of Estimating Radiation Doses with Sufficient Accuracy

The Secretary established the feasibility determination for the class of employees 

covered by this report based upon the findings summarized below.

 NIOSH has determined that the principal sources of internal radiation for 

members of the proposed class included exposures to uranium residues as well 

as African and domestic uranium ores through inhalation and ingestion of 

airborne uranium dust, and exposure from thorium, radium, radon and radon 

progeny.

 NIOSH has determined that based on the lack of thorium, radium, radon and 

uranium monitoring data for Clinton Engineer Works Elza Gate warehouse 

workers during the storage and/or repackaging operations conducted during the 

period from January 1, 1943 through December 31, 1949, internal dose 

reconstruction from all potential sources of exposure is not feasible.

 NIOSH has determined that the principal sources of external radiation for 

members of the proposed class included exposures to uranium ore, UO2

residues, uranium tailings, uranium slag, and uranium decay products that were 

stored at the Clinton Engineer Works Elza Gate warehouse site.

 Although limited external dosimetry data were found for 1945-1946, NIOSH has 

not identified sufficient documentation to define and quantify the total external 

source term for the Clinton Engineer Works Elza Gate warehouse area during 

the period from January 1, 1943 through December 31, 1949. Without additional 

documentation or source term information, NIOSH cannot make assumptions 

about the relative amounts of materials that would have been encountered at the 

site during this period, nor can NIOSH determine whether the monitored 

exposures are representative of the maximally-exposed individual during the 

period under evaluation. 

 Although no specific information regarding occupational medical dose has been 

identified for individual Clinton Engineer Works employees, the dose associated 

with medical X-ray exams, if required as a condition of employment and 

administered onsite, can be bound by using the assumptions and applicable 

protocols in the complex-wide Technical Information Bulletin, Dose 

Reconstruction from Occupationally Related Diagnostic X-Ray Procedures

(ORAUT-OTIB-0006). 

 NIOSH concludes that there is insufficient source term information and external 

monitoring data available to bound external exposures for the period from 

January 1, 1943 through December 31, 1949. NIOSH finds that it is likely 

feasible to reconstruct occupational medical dose for workers at the Clinton 

Engineer Works Elza Gate warehouse area with sufficient accuracy.
HHS Special Exposure Cohort Designation:

Clinton Engineer Works, Oak Ridge, Tennessee

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 NIOSH lacks sufficient information, which includes specific biological monitoring 

data, sufficient air monitoring information, sufficient process and radiological 

source information, and surrogate data from similar operations at other sites that 

would allow it to estimate the potential internal or external radiological exposures 

for all workers who worked at the Clinton Engineer Works Elza Gate warehouse 

area during the period from January 1, 1943 through December 31, 1949. 

NIOSH determined that members of this class may have received internal and 

external radiation exposures from uranium residues as well as African and 

domestic uranium ores, and uranium decay products, over the covered period at 

the site.

 NIOSH has documented that it cannot complete the dose reconstructions related 

to this petition with sufficient accuracy for the employees who worked at the 

Clinton Engineer Works Elza Gate warehouse area during the period from 

January 1, 1943 through December 31, 1949. The basis of this finding 

demonstrates that NIOSH does not have access to sufficient information to 

estimate either the maximum radiation dose incurred by any member of the class 

or to estimate such radiation doses more precisely than a maximum dose 

estimate for that period. As indicated in its research, NIOSH has identified that 

the class members include all employees of the Tennessee Eastman Corporation 

from 1943 through 1947, and the Carbide and Carbon Chemicals Corporation 

from 1947 through 1949, who worked at the Clinton Engineer Works.

 Although NIOSH found that it is not possible to completely reconstruct radiation 

doses for the proposed class, NIOSH intends to use any internal and external 

monitoring data that may become available for an individual claim (and that can 

be interpreted using existing NIOSH dose reconstruction processes or 

procedures) to support a partial dose reconstruction for non-presumptive cancers 

and/or cases that have less than 250 work days of employment. Therefore, dose 

reconstructions for individuals employed at Clinton Engineer Works in the area 

around the Elza Gate warehouses during the period from January 1, 1943 

through December 31, 1949, but who do not qualify for inclusion in the SEC, may 

be performed using these data as appropriate. 

 Pursuant to 42 C.F.R. § 83.13(c)(1), NIOSH determined that there is insufficient 

information to either: (1) estimate the maximum radiation dose, for every type of 

cancer for which radiation doses are reconstructed, that could have been 

incurred under plausible circumstances by any member of the class; or (2) 

estimate the radiation doses of members of the class more precisely than a 

maximum dose estimate.

 The Board concurred with the NIOSH evaluation and recommended the 

proposed class for addition to the SEC.
HHS Special Exposure Cohort Designation:

Clinton Engineer Works, Oak Ridge, Tennessee

Page 5

Health Endangerment

The Secretary established the health endangerment determination for the class of 

employees covered by this report based upon the findings summarized below.

(1) Pursuant to 42 C.F.R. § 83.13(c)(3), NIOSH established that there is a 

reasonable likelihood that such radiation doses may have endangered the 

health of members of the class. Pursuant to 42 C.F.R. § 83.13(c)(3)(ii), 

NIOSH specified a minimum duration of employment to satisfy this health 

endangerment criterion as “having been employed for a number of work days 

aggregating at least 250 work days within the parameters established for this 

class or in combination with work days within the parameters (excluding 

aggregate work day requirements) established for one or more other classes 

of employees in the Cohort.”

(2) NIOSH did not identify any evidence from the petitioners or from other 

resources that would establish that the class was exposed to radiation during 

a discrete incident likely to have involved exceptionally high-level exposures, 

such as a nuclear criticality incident, as defined under 42 C.F.R. § 

83.13(c)(3)(i). 

(3) The Board concurred with NIOSH’s finding that the health of the class may 

have been endangered and defined the class according to the 250-work day 

requirement specified under 42 C.F.R. § 83.13(c)(3)(ii). 

V. Effect and Effective Date of Designation

The Secretary submits this report on the designation of one additional class to the 

SEC for review by Congress, pursuant to 42 U.S.C. §§ 7384l(14)(C)(ii) and 

7384q(c)(2)(A), as amended by the Ronald W. Reagan National Defense 

Authorization Act for Fiscal Year 2005, Pub. L. No. 108-375 (codified as amended in 

scattered sections of 42 U.S.C.). Pursuant to 42 U.S.C. § 7384l(14)(C)(ii), as 

amended by the Ronald W. Reagan National Defense Authorization Act for Fiscal 

Year 2005, Pub. L. No. 108-375 (codified as amended in scattered sections of 42 

U.S.C.), the designation in this report will become effective 30 days after the date of 

this report’s submission to Congress “unless Congress otherwise provides.”

VI. Administrative Review of Designation

The health endangerment determination of the designation provided in this report 

may be subject to an administrative review within HHS, pursuant to 42 C.F.R. § 

83.18(a). On the basis of such a review, if the Secretary decides to expand the class 

of employees covered by this designation, the Secretary would transmit a 

supplementary report to Congress providing the expanded employee class definition 

and the criteria and findings on which the decision was based.